Five member oil immersion microscope objective

ABSTRACT

A five member microscope objective having a numerical aperture of substantially 1.25 and a magnification of substantially 100 X provides a substantially flat image field of 24mm.

on 3 9 oz 1 V I United States Shoemaker [54] FIVE MEMBER OIL IMMERSION MICROSCOPE OBJECTIVE [75] Inventor: Arthur H. Shoemaker, East Aurora,

[73] Assignee: American Optical Corporation,

Southbridge, Mass.

[22} Filed: May 6, I974 [21] Appl. No.: 467,437

[52] U5. Cl. 350/216; 350/175 ML; 350/176;

350/177 [51] Int. Cl. GOZB 21/02 [58] Field of Search..... 350/216, 175 ML, 176, 177

[56] References Cited UNITED STATES PATENTS 3,355,234 11/1967 Muller 350/175 ML X 51 Sept. 2, 1975 11/1970 Shoemaker 350/175 ML X 8/1971 Shoemaker 350/175 ML X Primary Examiner-John K. Corbin Attorney, Agent, or Firm-Alan H. Spencer; William C. Nealon; H. R. Berkenstock, Jr.

[5 7] ABSTRACT A five member microscope objective having a numerical aperture of substantially 1.25 and a magnification of substantially 100 provides a substantially flat image field of 24mm.

2 Claims, 1 Drawing Figure PATENTED SEP 2 I975 FIVE MEMBER OIL IMMERSION MICROSCOPE OBJECTIVE BACKGROUND OF THE INVENTION The lens parameters are as follows: The successive lens radii are designated RI-RI4 where a minus sign indicates radii on centers of curvature lying on the object side of their vertices. The axial thicknesses of successive lens elements are designated Tl-T9. The successive axial spaces from the object plane 14 are designated SI-SS. The refractive indices of the successive lens elements are designated NDl-ND9. The Abbe numbers of the successive lens glasses are designated achromatic oil immersion microscope objective having 1/1 119 sp tively.

a numerical aperture of substantially 1.25 and a magnification of substantially 100x, in which chromatic and spherical aberrations, coma, and astigmatism are well The above-mentioned parameters are related to the focal length according to the following constructional data:

corrected while yet providing a substantially flat image field of 24mm when used with a telescope objective as described in US. Pat. No. 3,355,234

DRAWING In the drawing, a microscope objective is represented by a plurality of lenses viewed transversely to their axis.

DESCRIPTION Referring now to the drawing, a microscope objective is generally shown at 2. It includes a front doublet 4, a single lens 6, a doublet 8, a doublet l0, and a doublet 12, all of said lenses being in axial alignment. Objective 2 is disposed relative to an object plane 14 as shown in the drawing. A capillary oil space exists between plane 14 and doublet 4. Positive doublet 4 includes a plane-convex lens I and a concave-convex lens II. Lens 6 is a concavo-convex positive meniscus shaped lens, also designated as III.

Doublet 8 includes a convex-concavo lens IV and a double convex lens V, together forming a positive double convex doublet. Doublet 10 includes a convexconcavo lens VI and a double convex lens VII, together forming a negative double convex doublet. Doublet 12 includes a double convex lens VIII and a double concave lens IX, together forming a negative convexconcavo doublet.

The foregoing parameters of radius, thickness and space are based on the value of F. As an example, the value of F is 1.830. Given in numbers, the foregoing data is as follows:

TABLE II Lens Radius Thickness Space S =0.33I6 R on I T,=0.625

R 1500 II T =2.920

S =0.O20 R -l L255 III T -,=2.000

S;,=O.300 R,,= l5.779 IV T,=I .200

R 8.298 V T;,=4.650

S =0.050 R 26.543 VI T,,=I .200

Rm 5.389 VII T =5.000 R -22.770

S -,=l4.7 I 2 R 55.430 VIII T, =2. I00

TABLE ll-Continued a second concavo-convex lens member ll,

said front and second members forming a doublet; Lens Radius Thickness Space a third concavo-convex lens member Ill IX 7 TFLgOO a fourth convex-concave lens member IV;

a fifth double convex lens member V; said fourth and fifth members forming a doublet;

a sixth convex concavo lens member W; a seventh double convex lens member Vll;

It will be apparent that the foregoing absolute values aid ixth and seventh members forming a doublet; are variable depending on the value of F. Other forms 10 n ei hth d ble onvex lens member VII; are thus possible and changes may be made in the vala ninth double concave lens member IX; ues of the constructional data based on the relationsaid eighth and ninth members forming a doublet; ships in th first f th above a Without d parting all of said lens members being axially aligned; and from the spirit of this invention. the parameters of lens radii (RI-R14), lens thick What is claimed is: nesses (Tl-T9), axial spaces among lens element 1. An achromatic microscope objective having a preand object plane (SI-S5), refractive indice determined magnification and a numerical aperture of (NDl-ND9), and Abbe numbers (111 1 9) bein; substantially 1.25 for forming an image of an object determined by the following relationship:

Refractive Abbe Lens Radius Thickness Space index Number s,=0.|812F RI x l T.=0.34|5F ND =l.5l700 u,=64.54

R 0.8197F I ll T =L59S6F ND. ;1.96028 3492 R l.5607F s. ,=0.0l09F R, 6.1503F lll T .,=1.0929F ND;,=l.78833 i =50.47

S;,=0.l639F R 8.6224F lV T,=0.6557F ND,=|.8049| v =25.42

R 4.5344F v T =2.5409F ND =L4865l u,,=84.46

S.,=0.0273F R 14.5044F v| T,,=0.6557F ND.,=|.80491 u.,=25.42

R,.,= 3.2l80F vn T,=2.7322F ND =l .4865] =s4.46 R.,-|2.4426F S -,=8.0395F R,. 30.2896F Vlll T,.=l.l475F ND =L74054 2759 R,;,=' 3.283IF ix T.,=0.9836F ND,,=l.6l328 v,,=44.28

R 4.1 I48F plane, said image being well corrected for spherical and wherein scalar values are given in millimeters and F 18 chromatic aberrations, coma, astigmatism and curvathe focal length of the objective in millimeters. ture of image field, said objective comprising: 2. The objective of claim 1 wherein F is 1.830.

a front plane-convex lens member I, 

1. An achromatic microscope objective having a predetermined magnification and a numerical aperture of substantially 1.25 for forming an image of an object plane, said image being well corrected for spherical and chromatic aberrations, coma, astigmatism and curvature of image field, said objective comprising: a front plano-convex lens member I, a second concavo-convex lens member II, said front and second members forming a doublet; a third concavo-convex lens member III a fourth convex-concavo lens member IV; a fifth double convex lens member V; said fourth and fifth members forming a doublet; a sixth convex concavo lens member VI; a seventh double convex lens member VII; said sixth and seventh members forming a doublet; an eighth double convex lens member VII; a ninth double concave lens member IX; said eighth and ninth members forming a doublet; all of said lens members being axially aligned; and the parameters of lens radii (R1-R14), lens thicknesses (T1-T9), axial spaces among lens elements and object plane (S1-S5), refractive indices (ND1-ND9), and Abbe numbers ( Nu 1 - Nu 9) being determined by the following relationship:
 2. The objective of claim 1 wherein F is 1.830. 